Player-piano-control apparatus



M, S. HOWARD. PLAYER PLANO CONTROL APPARATUS. APPLICATION FILED MAY|$11916.

1,339,848, Patented May 11, 1920.

3 SHEETS-SHEET I.

WITNESSES: lwE/vrok yg .wfiwazjffamfl 7% (5 m MKWM A TTOR/VEYS M. S.HOWARD. PLAYER PIANO CONTROL APPARATUS.

APPLICATION FILED MAY15, 1916.

1,339,848. Patsnixad- 3 SHEETSSHEET 2.

M. S. HOWARD.

PLAYER PIANO CONTROL APPARATUS.

APPLlCATlON FILED MAY 15, 1916.

Patented; May 11, 1920.

3 SHEETSSHEET 3.

[ar M 6 A TTOR/VEYS UNI-'IED STATES PATENT onnion.

MONROE S. HOWARD, 0F WAUKON, IOWA.

ILAYER-PIANU-CONTROL APPARATUS.

Application filed May 15,

To all whom it may concern Be it known that I, Mormon S. HOWARD, acitizen of the United States, and a resident of lVaukon, in the countyof Allamakee and State of Iowa, have invented a certain new and usefulImprovement in Player-Piano- (ontrol Apparatus, of which the followingis a specification.

It is well known to persons skilled in the art to which my presentinvention applies that the most common method of varying the loudness ofnotes in a player piano is to vary the tension of air used to operatethe striking pneumatics. Any degree of loudness may be obtained in thisway, but the chief disadvantage accruing to the simple and familiarplayer action resides in the vtact that all the notes are affected alikewhen the pressure is varied. The variations in the degrees of loudnessare customarily attained by the use of multiple wind chests or exhaustchambers, usually limited to two in order to avoid excessivecomplication, containing air maintained by suitable means at differentpressures, suitable types of selective devices being used for soundingcertain notes, such as melody notes, with the high tension air.

So far, however, to my knowledge, the results obtained have fallen farshort of the end sought, namely, the imitation of hand playing effectsand expressions, since only a few fixed degrees of loudness areobtainable, and even these limited degrees of loudness,'instead of beingavailable for individu ally controlling the degree of loudness withwhich the notes are struck, are useful only in affecting all or a greatnumber of the notes simultaneously. In order that the infinite varietyof expression and effects obtained in hand playing be reproduced, it isnecessary that any note be capable of being struck at any time with anydegree of loudness within the range of the instrument, whether struckalone or with other notes. It is necessary in order to accomplish thisresult automatically, to have the degree of vacuum attained in theindividual striking pneumaticsabsolutely under the control of theperforations in the music sheet, and to be able to obtain through thecontrol of the perforated music sheet, any degree of vacuum in any ofthe striking pneumatics and ind pendently of the rest of. them, anywhereSpecification of Letters Patent.

Patented May 11, 1920.

1916. Serial No. 97,614.

within the range of the various degrees of loudness which the instrumentis capable of producing.

l have developed what I believe to be an entirely new and novel methodof control for player pianos, by the use of which I make possible theduplication in mechanical playing, of the various expressions andeffects obtained in hand playing.

The system I have worked out for obtaining the individual control of thestriking pneumatics, provides for the employment of governors forcontrolling the degree of vacuum attained in the Pneumatics. Theprincipal object of my present invention is to provide an improved andnovel method of regulating the action of these governors.

A. further object of my present invention is to provide an improved andnovel method of applying the system of control to the action of thestriking pneumatics of a player piano.

ll'ith these and other objects in view which will become apparent as thedescription proceeds,-the invention resides in the construction,combination, and arrangement of parts hereinafter more fully describedand claimed, and illustrated in the accompanying drawings in which likecharacters of reference indicate like parts throughout the severalfigures, of which- Figure 1 represents diagrammatically the simplestform that the combination of parts used in obtaining the limitingpressure for the purposes of control, may take.

Fig. 2 represents diagrammatically, the application oi the system to theregulation, control, and adjustment of a governor which in turn may beused to limit the tension obtainable in still another system.

Fig. 3 represents diagrammatically a more detailed arrangement of thedevice.

4- represents a view in section taken tran. showing one method ofapplying the system to the control of the striking pneumatics.

Fig. 5 represents a fragmentary perspective view in detail, taken alongthe same section.

Fig. 6 represents a sectional view showing another method of controllingthe action of the striking pneumatics.

Fig. '7 represents a view in perspective of the governor valve removed,

ersely through a player piano action- Fig. 8 represents a plan View of asection of the tracker bar and music sheet used with this control. I

I11 acquiring the adjustment of the governor which controls the degreeof vacuum attained in its individual striking pneuniatic, it isnecessary that almost instantaneous adjustment be acquired for each notesounded. In acquiring the adjustment of the governor, I have resorted tothe use of a regulating or limiting pressure chamher (in practice theduct leading from the auxiliary opening in the tracker bar to thecontrol pneumatic of the governor) in which there is established, at thetime of striking the note, a pressure approximately that which isrequired in the striking pneumatic for striking the note. This pressurewill be somewhere between the limits defined on the one hand by theexternal atmospheric pressure and on the other hand by the pressuremaintained in the main eX- haust chamber or Wind chest. This pressure,acting on one side of the movable element of the governor pneumatic inopposition to the pressure which acts on the opposite side of thismovable element, which latter pressure is that which exists in thestriking pneumatic or other compartment in whiz h the pressure is to beregulated, furnishes the necessary force for operating the governorValve.

In order that an adjustable limiting pressure may be produced andmaintained in the pressure chamber, an orifice of fixed size is providedbetween the pressure chamher and the exhaust chamber or Wind chest, andan orifice of variable or adjustable size is provided between thepressure chamber and the external. air. Now if the orifice to theatmosphere is closed, the tension in the pressure chamber will becomethe same as that in the main exhaust chai er or wind chest, and if, onthe other hand, the orifice leading to the atmosphere is madesuiiiciently large in proportion to the orifice leading to the exhaustchamber, the tension within the pressure chamber will become practicallythe same as that of the atmosphere. The use of any size of orificeleadin? to the external air, between these limits. w ll result in theair in the pressure chamber rising; to, and remaining fixed at. such atension that the difference in pressure bct een the air in the pressurechamber and that in the exhaust chamber or wind chest on the one handand between the air in the pressure chamber and the external air on theother hand, will cause equal qiiiantities to flow into and out of thepressure chamher through the t o orifices.

n Fiog. 1 I have indicated diagrammatically the s mplest form which theinvention ma take in obtaining the limiting or controlling pressure forregulating the governor. In the figure, the chamber in which thelimiting or regulating pressure is to be established is indicated at25", and this chamber communicates through an opening 1-11: on the onehand with the external air, and through an orifice of fixed size 26 onthe other hand, with the duct l leading to a source of constant tension.While the ce 26 remains fixed, the orifice lei may dated by a needlevalve The source oi tension or pressure to which the duct 4- l may beeither above or below atmoseric pr 5S1ll'6,111(.l,3l11(50 it is usuallybelow atmospheric pressure, the explanation will be, for rear aons ofsimplicity limited to this case. Now when the pressure in the duct 4; islower than in the pressure chamber 25. air will flow from the pressurechamber through the ormce 26, thus reducing the pressure in tle pressurechamber, and consequently the atmosphem: pr 381110 will cause air toflow through the opening ill into the pressure chamber. The pressurethis chamber will continue to fall until lance is established. betweenthe rates at h the air is flowing in at the opening- 1-;- aiid out atthe opening By varyin; the size of the orifice 13:, various pressuresbecome almost instantaneously establishi-al in the pressure chamber 25.T he flow of the air through the orifice 1i varies with the area of theor e and the difference i10- lu'oen the pressures existing); on theoppositc sides of the opening. It has been found by mathematical calrulaion tha with the ll fire times the ".e of the opening- 2b. ave oixthsapproximately ot the total difference of pressure between that exist' 5in the dart l: and the external air can be utilized.

The laisic principle oi: obtaining. by my method, almostinstantaneously, the va ing forc s required for the control of thegovernas is seen, resides in the method oi ohta. fixed pres; ireintermediate the pres yes of a source of h pressure and the pressure ofa source of low pressure, by the use of apertuies, through one oi whichair fiows in from a source of hi 15h sure and through the other of wh chair ou into the source oi low pressure,

ions differences in pressure being ob- -.l h y'aryir'igr the area oi oneor both 0 ii the a pertures.

The application of this system to the re -ulation and variaoleadjustment of a 15 W- ernor, which in turn may be used to limit thetension. obtained. in another system. is iiulicated in Fig.2. Thegovernor consists of a pneumatic 18 by which a valve 20. ar ranged in aduct 21. which leads to atmosphere or a source oil exhaust, is operated.The pneumatic 18 is arranged in a char. 1.) which connects through aduct 19 with the system to be controlled. The pneumatic Ill) 18, beingin communication with chamber 25 through the duct 25", it will be seenthat the interior surface of the pneumatic is sub jected to the samepressure as exists in the chamber 25 while the exterior surface of thepneumatic is subject to the pressure ex isting in the chambe 19. Ii thepressure in chamber 19 is greater than in the chamber 25, the pneumaticwill be collapsed, and ii the pressure in 19 is less than that in 25 thepneumatic will be expanded. The movements of this pneumatic serve tooperate the valve 20. If the duct 21 leads to atmosphere, thearrangement will be such that. the valve will be closed when thepneumatic is collapsed, and hence, as the pressure is reduced in 19 thepneumatic 18, in opening upwardly, will open the valve 20, thus preventing a further reduction in 19 by admitting atmospheric air inthrough the duct 21 If the duct 21 leads to a source of exhaust then thevalve is so arranged that it will be open when the pneumatic iscollapsed. and the expansion of the pneumatic as the pressure in 19falls, will shift the valve to i'lUSl. the duct 21 thereby preventingfurther reduction of the pressure in 19. The particular form which thepneumatic 18 or valve 20 may take is optional with the user.

In Fig. 3, 5 represents a tracker bar in which an orifice 14,corresponding with the orifice in Figs. 1 and 2, is provided, saidorifice 14F being connected through a duct 25 with the pressure chamber25 A sheet 6 runs over the tracker bar and is provided with perforations16 of varying sizes and shapes designed to register with the opening 146as the sheet is drawn across the tracker bar, to produce the varyingsizes of orifices. The exhaust chamber 8 communicating with the pressurechamber 25* by the duct at, contains air at lower tension than theatmosphere, being adapted to be exhausted by means of the bellows 1,which connect by the duct 2 with the exhaust chamber 8. The duct 3 leadsfrom the exhaust chamber to the apparatus to be operated. Thisarrangement. shown diagrammatically in Fig. 3. represents, in general,the form I use for acquiring and controlling the expression in pneumaticpiano-playing apparatus. There are two distinct methods by which it maybe applied to the regulation or limitation of the force of the strokesof the individual. striking pneum'atics of the player action. and eachof these methods is subject to further sub-division.

The first method is by limiting the vacuum attained in the strikingpneumatic when a note is struck, and the second is by arranging adamping pneumatic so associated with the striking pneumatic as to beexpanded when the striking pneumatic is collapsed. wherebyto vary theforce ot the blow delivered by the striking-pneumatic. The first methodmay be accomplished in two ways, either by admitting directly air ofatmospheric pressure to the striking pneumatic to offset or retard theaction of the pneumatic, or by partially closing the passage throughwhich the air is exhausted from the striking pneumatic, thus varying theblow delivered. The first of these methods forms the subject of myPatent No. 1,190,172, dated July 5, 191b, and the second of these sub-:lorms of the first method described, is the subject of my Patent No.1,229.083. dated June 5, 1917.

The second main method of applying my system to the control of theaction of the striking pneumatics of a player piano. is represented inFigs. 4, 5, 6, 7 and 8. Referring more particularly to Figs. l and (i.the tracker bar 5*, duct 13. exhaust or tension chamber 8, primary valve11. secondary valve 12, passageway 10 and striking pneumatic 9,constitute the mechanism which is common in pneumatic piano playingapparatus, the operation of which, being well known, may be brieflydescribed as follows:

When air is admitted to the duct 13 by the registration of a perforationin the music sheet with the opening in the tracker bar with which theduct connects, the valve 11 is moved to close the opening in the exhaustchamber 8 and open that to the external air, and this in turn causes thevalve 12 to be shifted so as to establish communication between thepassageway 10 and the exhaust chamber 8, at the same time closing theoutlet to the external air, and the air is thus exhausted from thestriking pneumatic 9 through the passage 10, thereby col lapsing thestriking pneumatics to sound a note, the impulse being transmitted tothe piano hammer or key by the rod 35.

In the form shown in Fig. 4, the striking and damping pneumatics 9 and32 respectively are situated on opposite sides (ii a central stationaryleaf 15, being connected together by a link at, so that they will movein unison. The damping pneumatic is provided with a valve 31 to permitthe tree escape of air, as the pneumatic collapses, but which willprevent the inflow of air as the pneumatic 32 expands. The fixed leaf 15is provided with a chamber 19 having a pouch pneumatic 18 arrangedbetween it and a duct or passage 17, which communicates through a bleedhole 26 with the exhaust chamber 8. A duct 36 connects the chamber 19with the outside atmosphere, and arranged in this duct is the controlvalve 20 which has an opening 21 movable into positions for registrywith the duct or for not registering therewith, whereby to establish orclose communication through the duct. The valve 20 is shown in detail inFig. '7. and consists of a cylinder having pins or journals 22 at itsends whereby it is journaled for rotation. An arm 23 is carried by thevalve and extending out through a slot 24, is engaged by the free end orouter end of a lever 37 which, at its inner end, is connected by a link38 with a bracket 39 supported on one wall of the chamber 19. The lever37, as will be noted, lies in this chamber, and has a rod connecting itwith the diaphragm or pneumatic 18, so that when the pneumatic rises thelever will be raised, and as the pneumatic falls the lever will likewisefall, thus either opening or closing the valve 20. The tracker bar 5 isprovided with the usual openings 15, with which the tubes or ducts 13are in communication, and with the auxiliary openings 14 with which thetubes 41 communicate at their outer ends. The inner ends of the tubescommunicate each with the duct 17 in one of the striking pneumaticapparatus, these ducts as shown, communicating with the pneumatics 18below the latter.

The construction shown in Fig. (5 varies from that shown in Fig. 4,mainly in that the striking pneumatic and damping pneuinatics 32 have acommon movable element or leaf 33, so that one face of the leaf isexposed to the pressure existing in the striking pneumatic and the otherface is exposed to the pressure existing in the damping pneumatic. Thedamping pneumatic is provided with an opening leading to the atmospherewhich is closed by a valve 31, as already set out, with respect to Fig.4. In this instance, the duct 17 communicates with a duct 29 through thebleed hole 26. This duct 29 at one end communicates with the exhaustchamber 28, and at the other end communicates through a bleed hole 30with the damping pneumatic 32. In Fig. 4 the duct which corresponds withthe duct 29, communicates through a bleed opening with the chamber 19.These bleed holes are provided in each case for allowing the dampingpneumatic to normally assume the exhausted position, so that thepressure within it will be subject to the control of the governingsystem the instant the striking pneumatic begins to act. This is not,however, an essential part of the apparatus.

The operation of the control system in fixing the force of the stroke ofthe striking pneumatic, and thereby determining the loudness of the notestruck, may be briefly described as follows: At the same instant, orjust prior to the time when a perforation in the music sheet uncoversone of the openings 15 leading to duct 13 whereby to set in operationthe striking pneumatic, other perforations 16, which may be in the formof extensions of the regular perforations, uncover more or less of theauxiliary opening 14, thereby permitting the pressure in duct 41 to riseto the desired height, it being understood that, while the opening 14 iscovered by the sheet, the air is exhausted from this duct 41 and theduct 17 through the bleed hole 26. As the striking pneumatic 9 collapsesto strike a note, the force of its stroke is resisted and retarded bythe damping pneumatic 32, and the extent of the resistance offered bythe damping pneumatic is controlled by the pressure which exists in duct41, because when the pressure in the damping pneumatic 32 falls belowthat existing in duct 41 and pneumatic 18, the latter will expand andopen the valve 20 to a greater or less extent, thereby admittingatmospheric air to the damping pneumatic and thus preventing furtherincrease of the resistance offered thereby. Thus the resistance whichthe damping pneumatic offers to the stroke of the striking pneumatic, iscontrolled by the pressure existing in the duct 41 and the pressure inthis duct is under the control of the perforations 16 in the musicsheet. The lower the pressure established in the duct 41, the lower thepressure attained in the damping pneumatic 32, and hence the greater isthe resistance offered by it and consequently the softer is the notestruck. With increasing pressure in duct 41, louder notes are struck,since more air is admitted to the damping pneumatics, and hence lessresistance is offered to the striking pneumatic.

The action of each of the individual striking pneumatics of the piano,is thus under the control of the governing apparatus, and hence any notemay be struck at any time with any degree of force in the range betweenzero and the maximum, so that each note is thus independently under thecontrol of the governing apparatus.

In Fig. 6 the governor pneumatic 18 is in the nature of a bellows. beingprovided with an arm carried on the bellows leaf, which arm engages withthe arm 23 carried by the valve 20, so that the valve is thus controlledby the action of the bellows pneumatic. Either type of pneumatic may beused.

In order that equal increments of travel of the perforations in therecord sheet should produce equal increments of pressure in the chamber25. corresponding with the duct 41. the tracker bar openings increase inwidth in the direction of travel of the music sheet as indicated in Fig.8. As shown in this figure, the auxiliary openings 16 may be separatelyformed in the music sheet, or may form extensions or branches of theusual. perforations for coacting with the openings 15 in sounding thenotes of the piano.

Although I have described the preferred embodiments which my inventionmay take, I may desire to make such changes in the construction,combination, and arrangement of parts thereof, as do not departirom thespirit of the invention and the scope oi the appended claims.

I claim 1. Apparatus for controlling the striking pneumatic of a playerpiano including, a damper pneumatic operatively connected to the strikerpneumatic whereby to expand as the striker pneumatic contracts, a ductleading from the damper pneumatic to the atmosphere, a valve arranged inthe duct movable into positions "for closing and opening the duct, aduct leading from an auxiliary opening provided in the tracker bar tothe damper pneumatic, exhaust means consisting of a bleed hole arrangedbetween the last said duct and the exhaust chamber of the player piano,a governor pneumatic arranged across the last said duct, a leverpivotally arranged above the governor pneumatic and having connectiontherewith to be moved. as the governor pneumatic is moved, connectingmeans between the lever and the said valve whereby the movements of thegovernor pneumatic will control the movements of the valve, a checkvalve provided in the damper pneumatic tor allowing escape of airtherefrom as the damper pneumatic collapses, and adapted to preventreturn oi" air into the damper pneumatic, and a music sheet providedwith perforations for uncovering the auxiliary opening in the trackerbar to a greater or less extent for establishing various degrees ofpressure in the duct leading to the governor pneumatic.

2. Apparatus for controlling the striker pneumatics of player pianos,including a damper pneumatic operatively connected to the strikerpneumatic and controlling the force of the blows delivered by thelatter, a check valve carried by the damper pneumatic allowingexhaustion of air from the damper pneumatic as the latter collapses andpreventing reentrance of air into the damper pneumatic, a ductconnecting the damper pneumatic with the atmosphere, a valve arranged insaid duct which, when moved into one position, to allow passage ofatmospheric air through the duct and when moved into another positionclosing the passage through the duct, a pressure chamber having anexhaust opening of fixed size communicating with the exhaust chamber ofthe player piano, a control pneumatic arranged between the pressurechamber and the damper pneumatic, means connected with the controlpneumatic and with said valve for operating the latter as the controlpneumatic is actuated, a passage communicating with the pressure chamberand with an auxiliary opening provided in the tracker bar, and a musicsheet having auxiliary openings controlling the extent to which theauxiliary opening in the tracker bar is uncovered whereby to acquiredifferent degrees of pressure within the pressure chamber.

In an apparatus for controlling the action of the striking pneumaticsfor player pianos, the combination of a striking pneu matic, a damperpneumatic operatively c011- nected to the striking pneumatic andcontrolling the stroke of the striking pneumatic, means permittingescape of air from the damper pneumatic as it is collapsed, a passageconnecting the damper pneumatic with the atmosphere, a valve arranged insaid passage and adapted to be shifted into positions for opening andclosing the passage, a pressure chamber having an exhaust openingleading to the exhaust chamber of the player piano, :1 control pneumaticsubject to the pressure oi the pressure chamber, means carried by thecontrol pneumatic engaging the valve for operating the latter as thecontrol pneiunatic is operated, and music sheet controlled means foradmitting various quantities of air to the pressure chamber forobtaining different pressures therein, substantially as described.

a. In a control device for controlling the striking pneumatics of playerpianos, the

combination with the striking pneumatlc, of a damper pneumatic, a ductleading to the atmosphere, a valve arranged in the duct for controllingpassage therethrough, a source of exhaust, a pressure chamber having anopening of fixed size communicating with the source of exhaust, acontrol pneumatic arranged in communication with the pressure chamber,connecting means between the control pneumatic and said valve for operating the latter as the control pneumatic is operated, communicatingmeans between the pressure chamber and'the atmosphere, and means forvarying the size of last said communicating means whereby to acquiredifferent pressures within the pressure chamber.

MONROE S. HOVARD.

